Lecture 01

• What are the three major types of muscle tissues?

  Skeletal, smooth, and cardiac muscle
• What is the primary function of skeletal muscle?

  Producing movement and locomotion
• What is the neuromuscular junction (NMJ)?

  Connection between motor neuron and muscle fiber

  
• What is the structure of a skeletal muscle fibre?

  Includes sarcolemma, sarcoplasm, and myofibrils

  
• What is the role of the sarcoplasmic reticulum in muscle contraction?

  Stores and releases calcium ions

  
• What are the types of muscle fibers?

  Slow oxidative, fast oxidative, fast glycolytic
• What is a characteristic of skeletal muscle?

  Striated appearance due to sarcomeres
• How does smooth muscle differ from skeletal muscle?

  It has no striations and is involuntary
• What is a key feature of cardiac muscle?

  Contains intercalated disks and gap junctions

  
• What are the functions of muscles?

  Movement, posture, joint stabilisation, heat generation
• What is the sarcolemma?

  The plasma membrane of a muscle fibre
• What happens at the neuromuscular junction?

  Acetylcholine is released and binds to receptors

  
• What is the role of troponin and tropomyosin in muscle contraction?

  Regulate the binding of actin and myosin

  
• What is the crossbridge cycle?

  Process of myosin binding to actin and pulling

  
• What occurs during the sliding filament theory?

  Myosin and actin filaments slide past each other
• What is a twitch contraction?

  Contraction in response to a single action potential
• What determines the contractile force of a muscle?

  Number of fibre and individual fibre force
• What is tetanus in muscle contraction?

  Long-lasting contraction due to high stimulation

  
• What are the three major types of skeletal muscle fibers?

  Slow oxidative, fast oxidative, fast glycolytic
• What are the components of a myofibril?

  • Myofibril gives striated appearance
  • Sarcomere: repeated functional unit bordered by Z-line
  • Thick filaments: myosin
  • Thin filaments: actin
  • A-band: darker
  • I-band: lighter

  
• What are the actions of troponin and tropomyosin?

  • Troponin binds calcium ions
  • Tropomyosin covers myosin binding sites
  • Actin can bind to myosin when tropomyosin moves

  
• What is the arrangement of filaments in a sarcomere?

  • Thick filaments (myosin) in the center
  • Thin filaments (actin) on the sides
  • A-band remains constant during contraction
  • I-band shortens during contraction

  
• What is the temporal pattern of muscle contraction?

  • Latency phase: delay after stimulation
  • Contraction phase: crossbridge cycling
  • Relaxation phase: calcium uptake

  
• What factors influence muscle fibre force production?

  • Number of muscle fibre contracting
  • Individual fibre diameter
  • Frequency of stimulation
  • Type of muscle fibre
  • Extent of fatigue
• What is the hierarchy of muscle architecture?

  • Muscle fibre grouped into fascicles
  • Fascicles grouped into whole muscles
  • Connective tissue surrounds each level
• What is the regulation of muscle contractility?

  • Calcium ion concentration
  • Neurotransmitter release at NMJ
  • Fibre type characteristics

  
• What is the summary of muscle physiology?

  • Three types of muscle tissues
  • Muscle architecture and hierarchy
  • Regulation of muscle contractility
  • Temporal pattern of muscle contraction
  • Types of muscle fibre